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    <title>ShellCheck: SC2048 – Use `"$@"` (with quotes) to prevent whitespace problems.</title>
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    <h1>SC2048 – ShellCheck Wiki</h1>
    <a href="https://github.com/koalaman/shellcheck/wiki/SC2048">See this page on GitHub</a>
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    <h2 id="use--with-quotes-to-prevent-whitespace-problems">Use
<code>"$@"</code> (with quotes) to prevent whitespace problems.</h2>
<p>Or: Use "${array[@]}" (with quotes) to prevent whitespace
problems.</p>
<h3 id="problematic-code">Problematic code:</h3>
<div class="sourceCode" id="cb1"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb1-1"><a href="SC2048.html#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cp</span> <span class="va">$*</span> ~/dir</span>
<span id="cb1-2"><a href="SC2048.html#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="fu">cp</span> <span class="va">${array</span><span class="op">[*]</span><span class="va">}</span> ~/dir</span></code></pre></div>
<h3 id="correct-code">Correct code:</h3>
<div class="sourceCode" id="cb2"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb2-1"><a href="SC2048.html#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="fu">cp</span> <span class="st">&quot;</span><span class="va">$@</span><span class="st">&quot;</span> ~/dir</span>
<span id="cb2-2"><a href="SC2048.html#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="fu">cp</span> <span class="st">&quot;</span><span class="va">${array</span><span class="op">[@]</span><span class="va">}</span><span class="st">&quot;</span> ~/dir</span></code></pre></div>
<h3 id="rationale">Rationale:</h3>
<p><code>$*</code> and <code>${array[*]}</code>, unquoted, is subject to
word splitting and globbing.</p>
<p>Let's say you have three arguments or array elements:
<code>baz</code>, <code>foo bar</code> and <code>*</code></p>
<p><code>"$@"</code> and <code>"${array[@]}"</code>will expand into
exactly that: <code>baz</code>, <code>foo bar</code> and
<code>*</code></p>
<p><code>$*</code> and <code>${array[*]}</code> will expand into
multiple other arguments: <code>baz</code>, <code>foo</code>,
<code>bar</code>, <code>file.txt</code> and
<code>otherfile.jpg</code></p>
<p>Since the latter is rarely expected or desired, ShellCheck warns
about it.</p>
<h3 id="exceptions">Exceptions</h3>
<p>None.</p>
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